Switch-lock.



E. K.. POST.

SWITCH LOCK.

APPLICATION FILED APR. 16 1915.

11. 2Q? 25 Patented Dec. 5, 1916.

4 SHEETS-SHEET 1.

1NVEN'TOR ATTORNEY I E. K. POST.

SWITCH LOCK APPLICATION FILED APR. 16. 1915.

Patented Dec. 5,1916.

4 SHEETSSHEET 2.

INVENTOR E. K. POST.

SWITCH LOCK.

APPLICATION FILED APR. I6, 1915.

Patented Dec. 5, 1916.

4 SHEETS-SHEET 3.

INVEN'T'QR E ww m:

WW QNMN NM 9 mm WITNESS Wm A'ITVQVRNEY I E. K. POST.

SWITCH LOCK,

APPLICATION FILED APR. 16, 1915.

4 SHEETS-SHEET 4.

WITNESS SWITCH-LOCK.

Application filed April 16, 1915.

To all whom it may concern Be it known that I, EnNns'r K. 130241, a citizen of the United States, residing at Altoona, in the county of Blair and State of Pennsylvania, have invented a certain new and useful Switch-Lock, of which the following is a specification.

The purpose of my invention is to protect a railway switch from accidental displacement.

A further purpose of my invention is to electrically control a mechanically-operated switch lock at the switch, using electrical means preferably to interpose auxiliary mechanism rendering operative an otherwise inoperative lock release.

A further purpose of my invention is to provide a mechanically-operated switch lock lever with a plurality of fulcrums and to determine the operative fulcrum by outside, preferably electrical means. In the electrical control of the device I prefer to balance the lever so as to normally retain a fulcrumcarrying armature against the pole of a normally deenergized electromagnet.

A further purpose of my invention is to locate an electrically controlled switch lock between the switch points and the pipe line, preferably mounting it upon a switch and lock movement.

A further purpose of my invention is to apply indication locking to any of the various forms of my electrically controlled mechanically-operated looks.

I have preferred to illustrate my invention by application to but two of the different forms of switch-throwing and locking movements among the many for which it is evidently suitable and have selected for these movements locks of my invention which are practicable, efficient and relatively inexpensive and at the same time well illustrate the principles of. my invention.

, Figure 1 is a partly diagrammatic, partly top plan view of one construction embodying my invention. Fig. 2 is an enlarged top plan view of a portion of the structure seen in Fig. 1, the parts being in different posi tions. Fig. 3 is a section taken u on line 33 of Fig. 2. Figs. 4 and 5 are ragmentary sectional views corresponding to Fig.

3, showing the lever and locking parts in different positions. Fig. 6 is a section of Fig. 3 taken upon line 6--6 thereof. Fig. 7 is a section of Fig. 2 taken upon. line 7-7 thereof. Fig. 8 is a perspective view of the Specification of Letters Patent.

Patented net. .5, rain.

Serial No. 21,846.

locking bar shown. Fig. 9 is a diagramlmltie view of indication circuits used. Fig. 10 is a partly diagrammatic, partly perspective view of an application of my invention to another form of switch and lock movement.

In the drawings, like numerals designate corresponding parts.

I have pre erred to show my invention in one form as applied to switch-throwing and locking mechanism, invented by Amos R. Garber and shown in his patent of November 18, 1913, No. 1,079,120, for switch throwing and locking mechanism to which the first seven figures of my application are. directed.

In illustrating and describing hand thrown switch mechanisms cooperating with individual electric controlling levers (whatever the law of movement of the controlling levers) part of a miniature interlocking system, by which electrical contacts are made, I have not overlooked the fact that my inven. tion is also applicable to systems where both the controlling lever and the switch throwing lever are hand levers, as distinguished from power levers; or where both are power levers; or where major and not miniature interlocking is used; or where the lever by which my electrical control contacts are made is another locking lever and not a control lever alone.

I have illustrated my invention for convenience in connection with a well-known form of mechanical switch lever 1, here formingpart of a combination power and hand operated system with miniature interlocking and miniature lever control of a hand-operated switch lever such as is shown and described in my Patent No. 923,702 for interlocking switch and signal system, issued June 1, 1900. The lever is locked. by means of pins 2, 3, strip 4. and rod 5, with a controlling lever 6 of a miniature interlocking system utilizing electric locks 7 and 8, both of which perform combined detector andindication lock service, and lever 9, by which the rod 5 is thrown.

While the above mentioned Garber patent shows the form of switch throwing and locking mechanism with which my invention may he used to the best advantage I appreciate that the invention is also applicable to switch throwing mechanisms generally and, in illustration of this fact, show it as applied to one other form, selecting for the second illustration one of the other forms of switch throwing and operating mechanisms in general use.

The Garber mechanism is thrown by pipe line 10, rocker arm 11, pivoted at 12, and cross pipe connection 13. This connection is transverse to the track and often passes across one or more intermediate tracks to if the main pipe line had been pulled by its lever to a corresponding extent. Breaking of either allows the movement to bejarred to unintended positions. This accidental operation of Garber or other switch throwing and locking mechanisms is one of the dangers against which my invention herein is designed to protect.

The Garber mechanism is described in detail in his patent, to which reference is made. for any further information than is herein contained. It comprises, generally, a base 14, upon which are mounted the throwing mechanism for the switch operating rod 15 and a locking construction for the lock rod 16. The throwing mechanism includes a movable element, shown as a pair of spaced plates 17 having like slots 18 in them. The

edges of the slots at the turn are first utilized as cams for disengaging a pin 19 (secured to the switch operating rod 15) from either one of the end branches 20, 21 of like slots 22 in spaced fixed plates 28, then drive this pin through the central part of slots 22 and turn it into the other end branches 21 or 20 at the opposite end of the stroke. The pin is subsequently locked in position in the branches 21 or 20, of the slots 22 by engagement of the side surfaces 24 or of the slots 18 with the side of the pin.

During the moven'ient of the pin 15) the lock is unlocked, the lock rod 16 is moved by movement of the switch points and the lock is again engaged with the lock rod by means of the like slots 26 in the plates 17. The slots are provided at each end with branches whose side walls operate as cams, giving movement to the pin 27 by which the spaced strips 28 (forming together the looking element) are thrown to first disengage from the walls of notches in the rod 16, and, at the end of the stroke, to engage with other notches therein. The intermediate straight portions of the slots 26 retain the pin 27 and hence strips 28 in position, with the locking element disengaged from the rod 16, while the rods 15 and 16 are being thrown.

I have not considered it necessary to describe in detail the construction and connection of the switch points, the adjustment by which the rod 15 is set with respect to the switch points, the adjustments of size and position of the notches in the lock rod 16, the rollers upon the pins 19 and 27, the guides for the movable plates nor other details of plate separation and frame construction of the Garber device, as these are not altered by the present invention and are clearly set forth in one operative form in the Garber patent.

In applying my invention to the Garber switch throwing and locking mechanism, I extend the pin 19 at 30, above the upper surface, here plate 31, of the throwing part of the mechanism, in order that it may be enb shall call a lever because its function is most conveniently performed by a lever. It is to be rendered operative or inoperative at will to release the lock. In the form of my invention first illustrated I provide for movements of the lever which shall be effective or ineffective to release the lock, under outside control by giving the lever two pivot points, 37 and 38 as possible fulcrum points, and fixing one pivot as a fulcrum or allowing the lever to move bodily at this point, by means operated at a distance. The control shown is electric, through a circuit closed by contacts upon and about lever 6.

Obviously, the relative positions of the fulcrum points and cooperating or engaging member 39, here a. pin, which is engaged by the operating device 32, may be varied.

I have shown the pin as beveled at its end at 40 and 41 in substantial agreement with the bevcl of the double cam. In order to maintain the position of the pin and receive 1 the lateral thrust I pass it through guide l pivot it to the lever arm by a rather loose pivot at 43.

At the opposite end of the lever arm. I have illustrated the fulcrum 38 as located in a yoke 44 upon one end of a rod 45, whose opposite end is attached to an armature 46. The rod -15 for convenience is here shown as passing through an electromagnet 47 from whose core 48 the armature is slightly spaced 1 by the spool -19, in order that the arn'iature may not stick against the core.

The pivot 37 connects the lever with a locking bar 50, whose locking ends 51 are guided in slots 52 within frame members 53.

This slotted frame construction permits vertical movement of the locking bar and supports this bar against the side thrust of the extension 30 of pin 19 when the bar is performing its locking function. The guiding frame is rigidly secured with respect to the switch throwing mechanism.

The locking bar 50 is given considerable mass so as to avoid improper lifting of the bar and consequent failure of the locking function under circumstances hereinafter pointed out. This is done in the illustration by making it of much larger cross section between the ends than is required for the locking portions of the bar.

In order that arn'iature 46 may normally rest in the position shown in Fig. 8, so that the electromagnet, when magnetized will not have to draw the armature but will be required merely to retain it, the weight of the parts of and upon the lever to the right of the fulcrum point 37 in this Fig. 3 is made to exceed the weight of the parts of and upon this lever to the left of this fulcrum point. In

order to insure this condition beyond question, I have made provision which I. recognize will not ordinarily be necessary nor desirable, by extending the rod beyond the point of support of pin 39, as at 54 and mounting a weight 55 upon this extension. The weight is shown as adjustable along the lever to give more complete control over the distribution of mass in and upon the lever arm upon the two sides of fulcrum 37.

Theband 56 carried by the lever 6 is of such size and so positioned as to electrically connect the normally disconnected spring contacts 57 at an intermediate part of the stroke of the lever, e01 responding to the unlocked position of the lock 2, 3, 4. \Vhen these spring contacts are connected. the battery 58 energizes the electromagnet 47. retaining the armature 46 firmly in the position shown in Fig. 3. The subsequent throwing movement of the lever 1 is transmitted to the switch throwing plates 17, with immediate movement of pin 27 carrying operating member 32.

The early movement of pin 27 takes place before the extension 30 of pin 19 has been released from the side edge locking control of the surfaces 24 and 25 and consequently before the curved intermediate walls of this slot 18 engage the pin 19 to move it out of the end portions 20 or 21 in the slots of the fixed plates. The construction is so proportioned that the operating member 32 engages the pin 39 and lifts the lever 36 before the cam surfaces of slot 18 begin to move the pin 19.

If the electromagnet be energized. as will occur in the operation of throwing the switch from the tower, the lever 36 will be supported upon and swing about the fulcrum 38 and the lifting of the pin 39 will lift the locking bar, raising it from the locking position, its normal position shown in Fig. 3, to the level shown in Fig. 1 where the end 30 of pin 19 can move beneath it and travel beneath it to the opposite end of its stroke. This pin 19 will then rest in a position corresponding to that shown in Fig. 3, except that it will lie to the left of the end 51 of the locking bar, instead of to the right thereof, as shown in Fig. 3. The looking bar 50 will then drop to the position shown in Fig. 3 and again retain the pin 19 in position. Should the electromagnet not be energized, however. as would be the case with failure of the circuit or unauthorized or accidental movement of the pipes. such as would occur if the main or cross pipe line were bent by a drag or wreck upon an intermediate track, the lack of energization of the electromagnet would permit its armature to move freely to the position shown in Fig. 5. The lever 36 would therefore turn about the pivot 37 without lifting the locking bar from its initial locking position. The locking bar is deliberately made heavier than would be required for the locking function, in order that a sudden lifting impulse given to the pin 39 may not lift the locking bar 50 before the inertia of the magnet armature and connected parts have been overcome.

In the form shown in Figs. 1, 2, 3 and 7 I have provided indication locking controlled by the position of the locking bar 50 passing the circuits controlling the indication function of locks 7 and 8 through contacts at my lock in addition to passing them through the usual switch indication contacts between lock rod 16 and the locking member 28. The contacts to be made by my lock are mounted upon the frame members in duplicate, one set on each side. as shown at 59 and 60, 59 and 60 insulated at 61 and normally held in contact by straps 62, movable with the weighted lock member 51. so as not only to bring the contacts 59 and 60, 59' and 60 together when this locking member is in place but to give them some wiping movement and additional pressure together to keep the contacts clean and avoid separation by reason of vibration. These results can readily be obtained by slight corresponding additional weight in the locking member to overcome the additional lifting tendency of the spring contacts.

It will be evident from Figs. 3 and 7 that the contacts 59 and 60. 59 and 60 will be engaged when the operating member is at either extremity of its stroke. upon the right, as seen in Fig. 3. or upon the left. as the ,case may be. of the pin 39. since the locking bar 50 will be lowered fully in either case. The contacts of both pairs will remain in closed position when the lever 36 swings about the pivot 37 as a fulcrum. as

cause of the cnergization of the electromagnet 42, as in Fig. 4, so as to raise the locking member, the straps will be lifted free from the contacts and these contacts will resume the separated positions in which they would naturally lie but for the pressure of the straps.

In connection with the locking member 28 I show two pairs of contacts such as have previously been used for indication circuits. These comprise two pairs of spring contacts 63 and 64, 63 and 64: within the cover frame 65 over the lock. The contacts forming each pair are insulated from each other as well as from the other pair. Binding posts are provided for the contacts of these pairs, as also for the contacts 59, 60, 59 and 60'.

Upon the strips 28, which effect the locking function, are placed insulated conductors 66, 67 transverse to the path of movement of the strips 28, so as to engage contacts 63 and 64 and 63 and 64', respectively, at the extremities of movement.

The connections for the normal indication circuit of lock 8 are made through contacts 59 and 60, 63, 66 and 64 and the battery, as seen in Fig. 9. Correspondingly, the connections for the reverse indication circuit of lock 7 pass through contacts 59 and 60, 63, 67 and 64 and the battery. keeping the circuits distinct. I have not shown the detector circuits for these two locks. They are well understood in the art.

In the second form of my invention, illustrated in Fig. 10, I have applied my invention to switch points thrown by an escape ment crank 68 through the medium of a pin 69 upon a slide plate 70, moved in any suitable guides, as by rocker arms 71, 7 2, cross pipe line 73 and main pipe line not shown. The mechanical connections from the pipe line to the lever 6 may permissibly be the same as those of Fig. 1 and I have not changed the character of lever (6) shown in the illustration as the construction shown in my patent is adaptable to all forms of miniature interlocking levers and my patent shows this. The use of electrical contacts such as contemplated in this present invention upon one of the levers of another type would be a very simple matter. Obviously. the character of interlocking shaft makes no difference in the combination. Several bell cranks are illustrated because such a switch throwing mechanism is generally placed close to the switch points which it is to throw and must be pulled parallel to the length of the track.

The plate carries locking pins 74 and 7 5, locking with rod 76, apertured at 77 and 78. The rod is guided and supported against side strain by a guiding block 79.

My lock is here shown as mechanically operated by a. lover of the third class at all operative times since its selective fulcrum points 80 and 81 are at opposite ends of the lever and the power is applied between these two points. The armature 46' is above the electromagnet 47. The lever is here not extended and no additional weight is used. The operating member, here lifting element 32' is shown again as a double cam with cam faces 33, 34 and dwell 35 coiiperating with faces 40, 41 upon element 39', corresponding to the pin, which here also has a rest or dwell.

The locking rib or bar 82 normally lies within the path of travel of the lug 83 upon the plate 70 at such distances from the lug. in each direction of travel of the plate that the lug 83 will engage with this rib and stop before the points of'the pins 74 or 75. as it may be, (according to the direction of movement) release from the apertures 77 or 78 of the rod 76. The rib 82 is shown as reinforced against transverse strains by the abutments 84, 85, in fixed bars 86. The rib is weighted by a block 87, so as not to lift readily, in order that the rib may not be jarred out of its locking position by quick movement of the lifting element 32' when the electromagnet is not energized.

The armature 46 normally lies in substantial contact with the electromagnet 47, care being taken to avoid sticking. This insures that the magnet need not draw the armature from a distance but merely retain it. When the armature is tightly held against the electromagnet, fixing the fulcrum of the lever at 80, the bar 82 is lifted by the wedging action of the operating member 32 against the cooperating member 39.

The band upon the shaft 6 connects the spring contacts to complete the circuit for the electromagnet when the shaft 6 has re tated part of its stroke. Tn this position the circuit is closed through the battery and electromagnet 47 and ground. holding the armature to its magnet firmly while the switch is thrown. With the first movement of the plate 70, the double cam operating member 32' engages with the coiiperating member 39 upon the lever and lifts the locking bar 82 out of the way of the lug 83. The cooperating faces and 4-1 permit the lock to lower as the plate 70 moves further so that the locking bar 82 drops again to the position shown in Fig. 10 after the lug 83 has passed the bar. In the meantime, while the locking bar 82 is raised. the pins 74 and are disengaged from the openings in the lock rod 76 and the switch is thrown by means of the pin 69 engaging the escapement crank 68. At the end of movement of the switch, the pin 75 engages within the opening 77, locking the rod 76 at this point also.

Switch indication locking is secured by means similar to those shown in Figs. 1 to 9,

in addition to the usual pairs of insulated spring cont-act strips 88, 89 which are connected, one pair at each end of the stroke, by a contact piece 90. In view of the full illustration of the indication locking construction and circuits operated with my lock in Figs. 1 to 9, I have not considered it necessary to illustrate more than the straps and contact springs used, in Fig. 10.

It will be evident that the form of operating connections utilized by me is not vital provided that the lock is normally set and the connections are rendered operative by means separate from the switch throwing device and controlled from a distance so that local mechanically operated forces will release the lock. Electrical control is the most convenient form. The lever affords the simplest mechanical means of shifting the locking element and the movement of the fulcrum affords the best control of the lever. The form of lever is not of primal importance since the electromagnet and locking bar may occupy various positions along the length of the bar with respect to the operating means by which the bar is lifted.

It will be evident that the type of electromagnet is immaterial, provided it perform the function of electrically placing or retaining parts when energized while permitting different relations of the parts when not energized.

It will be evident that the type of construction used, the proportioning of the several parts, the support given against thrust, strains, etc., and many other features are matters of design dependent upon the type of switch throwing mechanism to which the invention is to be applied, the service conditions to which it is to be subjected, the type of operating member or lever selected by the designer, the distribution and extent of space available for this part of the mechanism, the materials selected and the individual preference of the designer.

It will further be evident that the various forms of power-operated switch or signal levers, rotary or sliding, may be adapted to receive my inventionas freely as they receive the electrical contacts and indication and detector locking systems now applied to them and that the detail of the tower mechanism for throwing the switch affects the application of my invention but little.

I am fully aware that the distant-operated means need not be electrical, even though power-operated, since the principles involved in the use of various types of power operation are well recognized and their substitution one for the other to accomplish like mechanical functions at the distant point are well understood.

Where I refer to the locking of the switch throwing mechanism, I do not understand that the lock must engage directly with the throwing mechanism but contemplate including thereunder interference with the movement of this throwing mechanism indirectly as well as directly, as by interference with any of the movable parts operated by it in the installation. It will be observed that I have referred to the lever 36 as moved by the switch throwing mechanism, whereas,

it is in fact thrown by the movement of an t5 associated. locking construction including slide bar 28 which is operated by the switch throwing mechanism. This \Vlll illustrate my view in this particular, as the switch throwing mechanism and slide bar are so in- 30 terrelated that the operation or interruption of the slide bar similarly affects the other.

It is so obvious that other movable parts could be blocked to lock my throwing mechanism that I have not considered it 35 necessary to illustrate the blocking of other parts than those shown.

Having thus described my invention, What I claim'as new and desire to secure by Letters Patent is 90 1. In a device of the character stated, a switch-throwing mechanism, a lock therefor,

a lever pivoted in the lock at an intermediate point, a second pivot for the lever on one side of the pivot in the lock and connections between the lever and throwing mechanism on the other side of the pivot in the lock to shift the lever.

2. In a. device of the character stated, a switch-throwing mechanism, a. lock therefor, a. lever pivoted in the lock at an intermediate point, a. movable second pivot for the lever on one side of the pivot in the lock, connections between the lever and throwing mechanism on the other side of the pivot in the lock to shift the lever and distant operated control for the second pivot, fixing it or permitting its movement.

3. In a device of the character stated, a switch-throwing movement, a lever and connections for throwing the same, a normally set lock for the movement, a normally inoperative release for the lock moved by the switch-throwing mechanism and separate distant-operated means for rendering the release operative as it is moved by the switch-throwing mechanism.

4. In a device of the character stated, a switch-throwing mechanism, a stop in the path of the throwing mechanism, a cam movable with'the throwing mechanism, an arm connected with the stop and engaged by the cam and electro-magnetic means for controlling the path of movement of the arm to cause it to lift the stop.

In a device of the character stated, a switch-throwing mechanism, a lock therefor, a release for the lock mechanically moved by the switch-throwing mechanism, but normally inoperative, when moved, to

' means each capable of operation from a distance for moving the arm and determining its path of movement to make movement of the arm ineffective, or effective to remove the stop from the path of the mechanism.

7. In a device of the character stated, a switch-throwing mechanism, a look therefor, a lever for shifting said lock, said lever being engaged by the switch-throwing mechanism and having variant fulcrum points and electrical means for selecting the fulcrum point to cause movement of the lever to shift the lock.

8. In a device of the character stated, a,

switch-throwing mechanism, a lock adapted to interfere with movement of the mechanism, a normally inoperative lever for movin said lock, fulcrumed to said lock, a movab le second fulcrum for said lever, electrical means for fixing the second fulcrum to render the lever operative and connections between the lever and the switch-throwing mechanism whereby the lever is actuated by the mechanism.

9. In a device of the character stated, a switch-throwing and locking mechanism, a lock for the switch-throwing part of the mechanism, a normally inoperative lever release for said lock, a cam mounted upon the switch locking part of the mechanism, cooperating connections between the cam and lever adapted to move it mechanically and electrical means for selecting the fulcrum point of the lever to render it operative to release the lock.

10. In a device of the character stated, a switch-throwing mechanism, a lock therefor, a multiple-fulcrum lever connected with the lock for releasing the same, cam operated connections between the switchthrowing mechanism and the lever for moving it mechanically and electrical means for selecting the operative fulcrum to render it operative or inoperative at will.

, 11. In a device of the character stated, a switchthro\ving mechanism, a lock therefor, a normally inoperative operating device for said lock, connections between the device and the switch-throwing mechanism to shift the device and electromagnetic means for rendering the device operative, when shifted, to release the lock.

12. In a device of the character stated, a switch-throwing mechanism, a lever and connections for operating it, a lock for the mechanism normally in locked position, a release for the lock adapted to be moved by the switch-throwing mechanism, but when moved normally inoperative to release the lock, a controller at the switch adapted to render the release mechanism operative and a lever and connections for operating the controller.

13. In a device of the character stated, aminiature interlocking lever, an electrical circuit closed thereby, a hand-operated lever controlled by the miniature lever, a switchthrowing mechanism thrown by the hand lever, a lock for the switch-throwing mechanism, a normally inoperative release for the lock mechanically operated by the switchthrowing mechanism, and an electrical control for rendering the release operative.

14. In a device of the character stated, a switch-throwing mechanism, a lock for the mechanism, a multi-fulcrum lever controlling -the lock, normally inoperative to move it and having one fulcrum point connected with the lock, an electromagnet, an armature therefor normally close to the electromagnet, and carrying a second fulcrum point for the lever, lifting connections between the switch-throwing mechanism and the lever and an electric circuit capable of energizing the electromagnet to retain the armature and fix the second fulcrum point of the lever.

15. In a device of the character stated, a switch-throwing mechanism, a lock therefor set by gravity, a guide for the lock supporting it against thrust of the part locked, a lever fulcrumed in the lock and normally inoperative to lift it, a second fulcrum for the lever, an electromagnet, an armature for the electromagnet, connections between the second fulcrum of the lever and the armature fixing the fulcrum when the magnet is energized and allowing it to move when the magnet is deenergized and lifting connections between the lever and the switchthrowing mechanism.

16. I11 a device of the character stated, a switch-throwing mechanism, a look therefor set by gravity, a guide and support for the lock, a lever fulcrumed in the lock and normally inoperative to lift it, a second fulcrum for the lever, an electromagnet, an a rmature for the electromagnet normally lying against the electromagnet, connections between the second fulcrum of the lever and armature fixing the fulcrum when the armature is energized and allowing it to move when the armature is deenergized and lifting connections between the lever and the switch-throwing mechanism.

17. In a device of the character stated, a switch-throwing and locking movement, a supplemental lock for the switch-throwing movement, a normally inoperative lever-operated release for said lock, connections between the switch locking part of the movement and the lever to move the lever and electro-magnetic means for rendering the lever operative to release the lock.

18. In a device of the character stated, a switch-throwing mechanism, a switch rod thrown thereby, a lock movable vertically and adapted in lowered position to stop the movement of the switch rod, a lever con nected with the lock and having variant fulcrum points, connections between the switch-throwing mechanism and the lever lifting it with movement of the mechanism, an electromagnet, an armature therefor carrying a possible fulcrum point for the lever which is movable with the arl'nature and inoperative as a fulcrum when the magnet is deenergized and means for energizing the electromagnet to hold this fulcrum point rigid, rendering the lever operative to lift the lock.

19. In a device of the character stated, a switch-throwing mechanism, a switch rod thrown thereby, a pin connected with the rod, a lock engaging the pin to prevent its movement, a lever, a fulcrum for one end of the lever, normally floating and thereby rendered inoperative as a fulcrum, electromagnetic means for fixing this fulcrum, an intermediate fulcrum connected with the lock and operating connections between the lever and the switch-throwing mechanism.

20. In a device of the character stated, a tower-operated switch throwing mechanism, a switch rod thrown thereby, a pin connected with the rod, a lock engaging the pin to prevent its movement, a lever, a fulcrum for one end of the lever, normally floating and thereby rendered inoperative as a fulcrum, separately tower-operated means for fixing this fulcrum, an intermemally inope ative mechanical release for the lock actuated by the switch-throwing mechanism, connections from the tower for throwing the switch-throwing mechanism and separately power actuated means for rendering the release operative when actuated by the switch-throwing mechanism.

22. In a device of the character stated, a switch-throwing mechanism, a lock therefor adapted to be moved vertically to release the look, a lever pivoted in the lock at one point and having a second pivot and connections between another part of the lever and the switch-throwing mechanism to shift the lever about the second pivot point to lift the lock and release it.

23. In a device of the character stated, a switch operating plate, a lock for preventing movement of the plate, supporting means for the lock against thrust, a lever fulcrumed in the lock, an electromagnet, an armature therefor, a second fulcrum for the lever movable with the armature, operating connections between the lever and the plate and electrical connections for energizing the magnet to fix the armature and thereby fix the second fulcrum.

ERNEST K. POST. Witnesses:

WM. STnnLL JACKSON, J. LUTHERIA KAUFFMAN. 

